ec14 blowing fuse

[bigmike]

Hi , got an older 2002 ec14 mini digger, so probably a peljob badged as a volvo.. Set of 6 fuses under the seat on the right hand side when your sat on it. top right fuse is 7.5 amp and keeps blowing. Thought it was fuel pump so changed that and some dodgy wiring from down that area. Now starts and runs ( checked fuel pump is pumping when i turn key ) but you can hear it change engine noise and runs for short time then runs uneven, some times it stops but if i turn it off i find fuse is blown and at that point i think the fuel pump has stopped ..... not sure now where to look ??? is that fuse in the circuit for fuel pump ?
Any help appreciated because i'm stressing and started looking at prices for another machine !!

[Muz]

Hi , got an older 2002 ec14 mini digger, so probably a peljob badged as a volvo.. Set of 6 fuses under the seat on the right hand side when your sat on it. top right fuse is 7.5 amp and keeps blowing. Thought it was fuel pump so changed that and some dodgy wiring from down that area. Now starts and runs ( checked fuel pump is pumping when i turn key ) but you can hear it change engine noise and runs for short time then runs uneven, some times it stops but if i turn it off i find fuse is blown and at that point i think the fuel pump has stopped ..... not sure now where to look ??? is that fuse in the circuit for fuel pump ?
Any help appreciated because i'm stressing and started looking at prices for another machine !!

The fuel pumps do fail in odd ways sometimes ... so they should be replaced if they are dodgy. Remove it from the digger and inspect/test it to determine this. The worst problem with them can be that they seem to work, and make a noise but dont actually pump anything because the flutter valves have failed or got some shit in them, or the coil doesent shift the oscillating pumping member fast enough to do any work, due to some coil problem.

If a fuse is blowing .. it will be a short on the pump feed line most likely .. that wiring goes brittle and cracks, its not too clever, and you will have to trace it back to the contact area where the short is happening

[bigmike]

The fuel pumps do fail in odd ways sometimes ... so they should be replaced if they are dodgy. Remove it from the digger and inspect/test it to determine this. The worst problem with them can be that they seem to work, and make a noise but dont actually pump anything because the flutter valves have failed or got some shit in them, or the coil doesent shift the oscillating pumping member fast enough to do any work, due to some coil problem.

If a fuse is blowing .. it will be a short on the pump feed line most likely .. that wiring goes brittle and cracks, its not too clever, and you will have to trace it back to the contact area where the short is happening

its had a problem for a long time. just turned off on its own , then turn key and restart with no problem. Six weeks ago turned off but from then on it started blowing fuses . Have changed earth wire to pump and replaced most of live feed that i can get to. fitted new pump , checked its running by turning key to left , and removed out pipe from inline filter and saw diesel pumping out. But still blows fuse after running for a few mins . Is it worth while looking at wiring under the key area ?

[Muz]

its had a problem for a long time. just turned off on its own , then turn key and restart with no problem. Six weeks ago turned off but from then on it started blowing fuses . Have changed earth wire to pump and replaced most of live feed that i can get to. fitted new pump , checked its running by turning key to left , and removed out pipe from inline filter and saw diesel pumping out. But still blows fuse after running for a few mins . Is it worth while looking at wiring under the key area ?

What else does that fuse control ? .. Random shut downs can be any of the control sensors, oil pressure, water etc .. or a failure of the engine ecu .. you may have more than one fault

[bigmike]

What else does that fuse control ? .. Random shut downs can be any of the control sensors, oil pressure, water etc .. or a failure of the engine ecu .. you may have more than one fault

think the old pump was working ok , but the fuse blowing and cutting out or slowing right down made me look at the fuel pump ,( only place i could think of electric and fuel problem being linked ) but cant find out what the fuse also covers. its a 2001 volvo so probably still a peljob sirius plus with volvo paint work. got 6 fuses , 2 side by side , 3 rows deep. its the top right 7.5 that keeps blowing . to test oil sensor do i simply disconnect from the block and see if it stops blowing fuse ?

[Muz]

to test oil sensor do i simply disconnect from the block and see if it stops blowing fuse ?

Hey now .. that would be too easy .. Volvo did follow Pel Jobs design pattern for quite some time .. and the later models I'm used to, did work on the basis that all the sensors went to ground to trigger a reponse on the engine ecu.. but that wouldnt blow a fuse .. so your issue must be related on the power + side of the control systems 7.5 isnt usually big enough for engine management stuff in my opinion, usually they start at 10 amps , so I'd look at other items .. is it a cab or canopy ?

[bigmike]

Hey now .. that would be too easy .. Volvo did follow Pel Jobs design pattern for quite some time .. and the later models I'm used to, did work on the basis that all the sensors went to ground to trigger a reponse on the engine ecu.. but that wouldnt blow a fuse .. so your issue must be related on the power + side of the control systems 7.5 isnt usually big enough for engine management stuff in my opinion, usually they start at 10 amps , so I'd look at other items .. is it a cab or canopy ?

its a canopy , canopy been of for a while as needed to go under a carport so its more cabriolet at the moment. Wire to light been disconnected and a plug on the end to rejoin when cab goes back on . might that be on same circuit ?
Not sure what you mean by " power + side " ?

Cheers Miike

[bigmike]

After thinking for a while presume you mean the positive side of wiring that could be shorting out.

[Muz]

After thinking for a while presume you mean the positive side of wiring that could be shorting out.

Yes Pel Jobs trunking was pretty poor ... look for cables that emerge from a shielded bundle, and that go off to various relays, etc .. where the wires emerge and separate and perhaps rub against a metal panel, those are prime suspects for chaffing, also look for any that run alongside or across pipes, on a machine of that age it would be the first place to look and see if something is getting grounded, which would blow your fuse. Get the seat off and get a damn good look in there with a torch, cant remember if you said it was still running or not, but do it with the engine running and see if you can cause it to shut down by moving stuff about, bit by bit, be very methodical

[bigmike]

Yes Pel Jobs trunking was pretty poor ... look for cables that emerge from a shielded bundle, and that go off to various relays, etc .. where the wires emerge and separate and perhaps rub against a metal panel, those are prime suspects for chaffing, also look for any that run alongside or across pipes, on a machine of that age it would be the first place to look and see if something is getting grounded, which would blow your fuse. Get the seat off and get a damn good look in there with a torch, cant remember if you said it was still running or not, but do it with the engine running and see if you can cause it to shut down by moving stuff about, bit by bit, be very methodical

Will try that tomorrow afternoon if i get time . Need to go out to price 3 jobs up tomorrow so i'll do them first instead of going out to see them covered in dirt and old oil stains !! It will run for a few minutes before blowing fuse so might have chance to try some " cable wiggling " with it running.
Thanks for the help ,cheers Mike

[bigmike]

Update

Managed to find time yesterday to wire up new fuel pump , fump pumping as i can see it gurgling in see through in line filter , turned key and had it running. Tried wiggling wires looking for a short but nothing found yet.
Did notice that on starting the temperature light did not show on dashboard.
This morning oil , battery and heater plug light did light up . But after a few tries of turning ignition switch oil light didnt come on. Then noticed sometimes that heater plug light doesnt come on. Thought that should come on every time i turn ignition switch to the left ? Battery light comes on evrey time . Age old thing , own a machine for too long and you stop noticing things !!

Having read other threads on here , could i be looking at a switch problem or is there a starter relay ? Dont know much about this kind of electrics or what i'm looking for. Selection of boxes under seat near engine side , one is a safety type thing that shuts machine down if something fails i think.
Or could it be a temp or oil sender unit problem

[bigmike]

2 nd update ....

Had battery charger on as its been played with and done a lot of starts then cutting out so not charged itself back up.
Turned key and battery and oil light are on when key turned to 1st stage to right Still no temperature light ??
Had it running for a few minutes.
Runs fine for a while , then blows 7.5 amp fuse , engine note changes as fuel pump now stopped pumping so its running on fuel being pulled by injector pump i presume.
Also servo levers for front arms stop working aswell.
Could fault be temp sender ? And where is it on the engine ??? Not down the "other side " surely

Leaving digger alone to think about its actions and going for chips from nearest chip shop as stress relief

[bigmike]

Finally had to get a grown up to help with this. Took it to auto electrician.....

No wonder i was having problems with finding whats wrong, he found temperature sender unit was faulty and causing the intermittent turning off. Then also found solenoid ,that controls oil flow controlled by lifting the left side arm up , was blown and that was blowing the fuse.

changed temp and oil switches on the engine as the oil was also showing possible fault , new solenoid for £32 instead of buying whole unit from volvo for £210.

Almost back to normal !!

[Muz]

new solenoid for £32 instead of buying whole unit from volvo for £210.

Almost back to normal !!

Sounds a bit more encouraging .. can you give us some detail of the solenoid ? make etc ?

[bigmike]

Sounds a bit more encouraging .. can you give us some detail of the solenoid ? make etc ?

Auto electrician said it looked like a regularly used size , and sent me off to see local firm that repaired hydraulic tail lifts.
i had undone the whole solenoid and threaded section that undid from out of the hydraulic block and took something resembling a valve/switch with the solenoid on with me. the solenoid simply prized off the fitting and then slid new one on. fitted it back into hydraulic section under floor plate , then tightened up nut at the other end of solenoid once in position as it made fitting easier.
Make didn't seem to matter , main thing was 12 volt , same internal diameter and length of inside of solenoid.one he gave me was a couple of mill short so i fitted a thick washer behind the nut so it would tighten.
As you;ve said before.... £32 better than whole new unit for £210 !!!

Runs ok now

Next problem to solve , button on left side control that operates lever between swivel and altering off set , has been wrong for a time but now has stopped. is that button wired to a solenoid / switch and if so , where abouts. looked under floor pales but can't see anything ?
Cheers Mike